Abstract Introduction Coronavirus disease 2019 (COVID-19) has claimed millions of lives. Adequate protection of the professionals involved in patient care is essential in the battle against this disease. However, there is much uncertainty involving safety-relarted topics that are of particular interest to the rhinologist in the context of COVID-19. Objective To evaluate the current evidence regarding three safety-related topics: mask and respirator use, performance of nasal endoscopic procedures, and use of topical nasal and intranasal medications (saline irrigation and nasal corticosteroids). Methods A literature review was performed on the PubMed, Scopus, and Cochrane databases, with standardized search queries for each of the three topics of interest. Results In total, 13 articles on mask use, 6 articles on the safety of nasal corticosteroids, 6 articles on the safety of nasal endoscopic procedures, and 1 article on nasal irrigation with saline solution were included in the final analysis. Conclusion N95 respirators are essential for the adequate protection of otolaryngologists. If reuse is necessary, physical methods of sterilization must be employed. No evidence was found to contraindicate the use of nasal corticosteroids, whether acute (in the management of sinonasal inflammatory conditions) or continued (in patients who use them chronically). Nasal irrigation with saline solution apparently does not increase the risk in the context of COVID-19. Nasal endoscopic procedures should only be performed after testing the patient for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the surgical team must wear full personal protective equipment to prevent aerosol exposure.

INTRODUÇÃO: Diversos estudos experimentais evidenciam osteíte após estabelecimento de sinusite, corroborando para a ideia de que o envolvimento ósseo poderia participar na disseminação e perpetuação do processo inflamatório. Porém procedimentos realizados para indução da doença nestes modelos, como antrostomias, podem, por si só, desencadear osteíte. OBJETIVO: Avaliar osteíte em um modelo de rinossinusite em que não ocorre manipulação sinusal e verificar se esta é limitada ao lado de indução, ou se acomete o lado contralateral. MÉTODO: Estudo experimental em que induziu-se rinossinusite em 20 coelhos, por meio de obliteração temporária com esponja de uma das cavidades nasais. Amostras de tecido sinusal foram submetidas à análise histológica semiquantitativa, após sacrifício dos animais em intervalos regulares. RESULTADOS: Foram observados sinais de inflamação óssea e mucosa mais intensa no lado de indução, mas também contralateral. Testes estatísticos evidenciaram correlação entre a osteíte de ambos os lados, porém não entre inflamação óssea e mucosa de um mesmo lado, apoiando a teoria de que a inflamação poderia se disseminar através do tecido ósseo, independente da inflamação mucosa. CONCLUSÃO: O presente estudo evidenciou a existência de osteíte, tanto no lado de indução quanto no contralateral, em modelo experimental em que não ocorre manipulação sinusal.

INTRODUCTION: Several experimental studies have shown osteitis after the onset of sinusitis, supporting the idea that bone involvement could participate in the dissemination and perpetuation of this inflammatory disease. However, procedures commonly performed for the induction of sinusitis, such as antrostomies, can trigger sinusitis by themselves. OBJECTIVE: To evaluate osteitis in an animal model of sinusitis that does not violate the sinus directly and verify whether this is limited to the induction side, or if it affects the contralateral side. METHODS: Experimental study in which sinusitis was produced by inserting an obstructing sponge into the nasal cavity of 20 rabbits. After defined intervals, the animals were euthanized and maxillary sinus samples were removed for semi-quantitative histological analysis of mucosa and bone. RESULTS: Signs of bone and mucosal inflammation were observed, affecting both the induction and contralateral sides. Statistical analysis showed correlation between the intensity of osteitis on both sides, but not between mucosal and bone inflammation on the same side, supporting the theory that inflammation can spread through bone structures, regardless of mucosal inflammation. CONCLUSION: This study demonstrated that in an animal model of sinusitis that does not disturb the sinus directly osteitis occurs in the affected sinus and that it also affects the contralateral side.

Introdução: A realização de modelos experimentais nasossinusais em animais vem sendo realizada há décadas, com substancial aumento nos últimos anos. Tem como objetivos identificar as alterações fisiopatológicas ocasionadas pelo processo infeccioso sinusal e avaliar a eficácia de medicamentos no tratamento da rinossinusite. Objetivo: Avaliar a eficácia do modelo experimental proposto para a indução de um processo infeccioso nasossinusal agudo bacteriano, utilizando parâmetros histopatológicos e cultura da secreção sinusal. Método: Estudo experimental com 22 coelhos da raça Nova Zelândia, divididos em: grupo A (6 coelhos), grupo B (7 coelhos), grupo C (7 coelhos) e grupo D (controle com 2 coelhos).Induzido quadro de rinossinusite através da inserção de esponja sintética nas fossas nasais direita dos 20 coelhos (grupos de estudo), seguido por instilação de toxoide bacteriano (50% estreptocócico, 50% estafilocócico). Os grupos foram sacrificados com 10 dias (grupo A), 17 dias (grupo B) e 30 dias (grupos C e D). Resultados: Todos os coelhos do grupo de estudo apresentaram quadro de rinossinusite aguda bacteriana, através da identificação macroscópica, análise histológica e cultura das secreções. Conclusão: O modelo proposto apresenta simplicidade técnica para sua execução, similaridade ao quadro rinogênico que acomete os humanos e é altamente eficaz na produção de um quadro infeccioso bacteriano agudo sinusal.

Introduction: For decades, animals have been used in sinonasal experimental models, and the practice has increased substantially in the last few years. This study aimed to assess the pathogenesis of infectious process and medication efficiency to treat rhinosinusitis. Objective: To evaluate the efficiency of the proposed experimental model to induce an acute bacterial sinonasal infectious process through histological analysis and sinus secretion cultures. Methods: This was an experimental study with 22 New Zealand rabbits, divided into: group A (six rabbits), group B (seven rabbits), group C (seven rabbits), and group D (control group with two rabbits). Rhinosinusitis was induced by the insertion of a synthetic sponge into the right nasal cavity of 20 animals (study groups), followed by the instillation of bacterial strains (50% Staphylococcus sp. and 50% Streptococcus sp.). The groups were euthanized within 10 days (group A), 17 days (group B), and 30 days (groups C and D). Results: All the rabbits of the study group developed acute bacterial rhinosinusitis, which was diagnosed through macroscopic evaluation, histological analysis, and sinus secretion culture. Conclusion: The proposed model is technically simple to perform, it is similar to the rhinogenic model in human beings, and it is highly efficient to reproduce an acute bacterial sinus infection.